Posted by M. W. Myers, D.V.M. on March 05, 2001 at 08:41:24:
In Reply to: club rotation vs. laminitis rotation posted by Maggie Mieske on March 05, 2001 at 08:08:46:
: Hi folks,
: I posted on the general discussion board over the weekend about a horse we are trying to figure out and maybe I should have posted here. I got a few helpful responses and thank everyone for that. In brief, we suspect the horse has Cushing's however it is the opposite end of Cushing's where the horse has a fat, cresty neck, lumpy body, very overweight, etc. Not your typical case. Here's the dilemma...though laminitis has not been a serious issue as of yet with this horse (she did have a bout with an abcess last fall), she also has a club foot. Right now she is sore all over. The owner is very concerned about laminitis. However, her pulse is great in all her feet and there is no heat at all. My farrier husband does not feel that laminitis is the problem...X-rays showed 10-15 degrees (not cm) of rotation in the club foot and very little if any in the other. This is not typical of foundered feet. Foundered feet would show rotation in both feet not just one. Is this not correct? As I stated in my other post on the general discussion board, we don't want to jump the gun with corrective shoeing before identifying the source of her problem. Nelson has kept the club foot trimmed regularly and it would take someone with an experienced eye to tell it is a club foot. The horse does not test sore on the soles. But she IS sore all over and has a hard time walking though she will bear weight on her feet. Any experience helping horse owners and vets understand the difference between rotation in a club foot vs. rotation in foundered feet would be helpful. Or any comments proving us wrong...we want to help this horse and have provided you with our observations. The owner and I are using a glucometer today to check blood glucose before and after feeding her a grain meal before the vet does further Cushing's testing (I am leary of the dexamethazone suppression test and would prefer they do the rhythm test which Dr. Myers has mentioned on these bulletin boards). I am also leaning toward diet and nutrition as initial treatment vs. immediately putting her on drugs. She was on thryoid meds for about a year and has been taken off but we wonder if that may have exacerbated the condition rather than helped it! Thank you in advance for all comments, suggestions, advice...
: Maggie Mieske
Cushingoid and laminitic horses may not respond painfully to hoof testing. They also may not respond to phenylbutazone. Any time I get a low thyroid level on a horse I immediately test for Cushing's with a rhythm test. This test is more sensitive and far safer than a dexamethasone suppression test. An ACTH test may work on this horse as she appears to have been Cushingoid for some time now.
I would opt for Permax at a beginning dose of 1mg daily. It would be wonderful if dietary management would work, but you simply don't have the time at this juncture. Cushingoid horses can be very painful without rotation. The pain seems to originate from deep flexor tendon pull and is often not evident on the sole, especially if the horse has good hoof mass.
Blood glucose is nearly always normal or only slightly elevated. Horses utilize volatile fatty acids along with glucose for energy and have lower glucose values than humans or many other domestic animals. Cattle are even lower. I have only tested 3 Cushingoid horse with elevated blood glucose and none over 200mg/dl. It isn't a very helpful test in the equine.
You will need to change to a high protein, high fat, low carbohydrate feed. I also supplement with magnesium (Bioplex magnesium from Ukele Animal Health) and chromium (chromium proteinate-experimental product I have from EquiAide Laboraties). A short course of antibiotics may also be of benefit to lower the Streptococcal organisms in the cecum. I use Naxcel, two bottles, to give eight days of medication. Ampicillin can also be used and I have used 4 grams twice daily for 6 to 10 days.
Phenylbutazone is helpful for allevation of some inflammation even if you don't see immediate pain reduction. Do not allow the horse out of the stall when on antiinflammatories.
I can be reached through the consulting area of this site if you need further assistance.
M. W. Myers, D.V.M.